Residents of a sprawling housing estate in Manhattan are experiencing The Attack of the Killer Ladybirds. The swarm of insects is not the plot of a horror film but an organic alternative to traditional pesticides.

About 720,000 of the red and black beetles were released into the heart of the densely populated 80-acre Peter Cooper Village and Stuyvesant town complex to feast on other insects infesting the property.

“It’s a good idea,” said Irving Goodman, who has lived on the estate since it was built for returning soldiers after the Second World War. “I’m on the seventh floor. I don’t think they’ll bother me.” But another resident, who refused to give his name, lamented that the tiny predators could not eat the ubiquitous New York city rat.

Ladybirds got their name in the Middle Ages when farmers noticed that they fed on pests on their grapevines and called them “birds of Our Lady”. They eat greenfly, blackfly, insect eggs, small caterpillars and other soft insects that can damage the plants they sometimes feed on themselves.

“It’s a lot of fun,” said Glenn Mahoney, a senior director of Tishman Speyer, which recently bought the 110-block complex just to the north of East Village. “It’s pretty common in much smaller uses in residential gardens. We’re scaling it up.”

Each ladybird can munch up to 50 pests a day. “I think they’re on to something,” said Jay Feldman, director of Beyond Pesticides, a lobby group that promotes pesticide-free zones. “Increasingly, people are realising that synthetic pesticides are associated with a range of adverse effects, from nervous system disorders to cancer.”

The ladybirds were sent across the United States in mesh bags filled with wood shavings, each holding a cluster of 72,000, by a natural gardening company in Bozeman, Montana.

The species of ladybirds – as suggested by its Latin name Hippodamia convergens – converges by the millions in the wilderness in the footbills of the Sierra Nevada mountains in Oregon, California and Montana, where they are harvested by collectors.

By the time they arrived in Manhattan “they were lively and ready to eat anything that was not too quick for them”, said Eric Vinje, the owner of Planet Natural, the company that provided them. “This one is not prone to entering homes.

“In most cases, we reach for a can of pesticide and we kill not only the bad guys but the good guys, too,” he said. “All we’re doing here is putting more of the good guys to tip the scale, to get some kind of pest population control.”

Car owners will also benefit. “Ladybugs are known to eat aphids. Aphids can infest trees and produce a sticky, sap-like substance that can fall on to cars and harden,” said Warner Johnston, a spokesman for the New York Parks Department.

A taste for aphids

— Hippodamia convergens eat up to 50 aphids each a day

— Female ladybirds can lay 1,000 eggs twice a year. These hatch into larvae that feed for 30 days before entering the pupal stage

— The larvae – which look nothing like their attractive parents – are voracious eaters and consume their own weight in aphids every day

— A half a pint glass of ladybirds, about 4,500, will keep an area of 3,000 square feet (280 sq m) clear of aphids

Source: www.planetnatural.com; Cornell University

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